similar to: [PATCH 00/14] virtio: console: Hot-unplug fixes

Hello, This series fixes a few bugs and races with port unplug and the various file operations: read(), write() and close(). I started coding up an alternative locking mechanism based on the discussion earlier in this series, but some of what we already have has to remain, and the new code is sufficiently different, so I'd rather it bakes for a while, and I ensure there are no regressions

Hello, This series fixes a few bugs and races with port unplug and the various file operations: read(), write() and close(). I started coding up an alternative locking mechanism based on the discussion earlier in this series, but some of what we already have has to remain, and the new code is sufficiently different, so I'd rather it bakes for a while, and I ensure there are no regressions

Hello, This series fixes a few bugs and races with port unplug and the various file operations: read(), write(), close() and poll(). There still might be more races lurking, but testing this series looks good to at least solve the easily-triggerable ones. I've run the virtio-serial testsuite and a few open/close/unplug tests, and haven't seen any badness. I've marked these patches

Hello, This series fixes a few bugs and races with port unplug and the various file operations: read(), write(), close() and poll(). There still might be more races lurking, but testing this series looks good to at least solve the easily-triggerable ones. I've run the virtio-serial testsuite and a few open/close/unplug tests, and haven't seen any badness. I've marked these patches

Hello, This series fixes a few races with port unplug and the various file operations: read(), write(), close() and poll(). There still might be more races lurking, but testing this series looks good to at least solve the easily-triggerable ones. I've run the virtio-serial testsuite and a few open/close/unplug tests, and haven't seen any badness. I've marked these patches for

Hello, This series fixes a few races with port unplug and the various file operations: read(), write(), close() and poll(). There still might be more races lurking, but testing this series looks good to at least solve the easily-triggerable ones. I've run the virtio-serial testsuite and a few open/close/unplug tests, and haven't seen any badness. I've marked these patches for

Hey Rusty, Here are a few fixes for virtio and virtio_console. The first patch ensures the data elements of vqs are properly initialised at allocation-time so that we don't trigger BUG_ONs. I found this when hot-unplugging ports and there was just one unused buffer. detach_unused_buffers() kept returning pointers that were invalid. I didn't catch this earlier as I had the in_vq filled

Hey Rusty, Here are a few fixes for virtio and virtio_console. The first patch ensures the data elements of vqs are properly initialised at allocation-time so that we don't trigger BUG_ONs. I found this when hot-unplugging ports and there was just one unused buffer. detach_unused_buffers() kept returning pointers that were invalid. I didn't catch this earlier as I had the in_vq filled

On 07/19/2013 04:16 AM, Amit Shah wrote: > We used to keep the port's char device structs and the /sys entries > around till the last reference to the port was dropped. This is > actually unnecessary, and resulted in buggy behaviour: > > 1. Open port in guest > 2. Hot-unplug port > 3. Hot-plug a port with the same 'name' property as the unplugged one > >

On 07/19/2013 04:16 AM, Amit Shah wrote: > We used to keep the port's char device structs and the /sys entries > around till the last reference to the port was dropped. This is > actually unnecessary, and resulted in buggy behaviour: > > 1. Open port in guest > 2. Hot-unplug port > 3. Hot-plug a port with the same 'name' property as the unplugged one > >

Turns out virtio console tries to take a buffer out of an active vq. Works by sheer luck, and is explicitly forbidden by spec. And while going over it I saw that error handling is also broken - failure is easy to trigger if I force allocations to fail. Lightly tested. Michael S. Tsirkin (6): virtio_console: don't tie bufs to a vq virtio: add ability to iterate over vqs virtio_console:

Turns out virtio console tries to take a buffer out of an active vq. Works by sheer luck, and is explicitly forbidden by spec. And while going over it I saw that error handling is also broken - failure is easy to trigger if I force allocations to fail. Lightly tested. Michael S. Tsirkin (6): virtio_console: don't tie bufs to a vq virtio: add ability to iterate over vqs virtio_console:

On 07/19/2013 01:02 PM, Amit Shah wrote: > On (Fri) 19 Jul 2013 [11:21:47], Jason Wang wrote: >> On 07/19/2013 04:16 AM, Amit Shah wrote: > >>> diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c >>> index b04ec95..6bf0df3 100644 >>> --- a/drivers/char/virtio_console.c >>> +++ b/drivers/char/virtio_console.c >>> @@

On 07/19/2013 01:02 PM, Amit Shah wrote: > On (Fri) 19 Jul 2013 [11:21:47], Jason Wang wrote: >> On 07/19/2013 04:16 AM, Amit Shah wrote: > >>> diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c >>> index b04ec95..6bf0df3 100644 >>> --- a/drivers/char/virtio_console.c >>> +++ b/drivers/char/virtio_console.c >>> @@

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Use virtio device index for creating unique device port names. Current index allocation in virtio is based on a monotonically increasing variable "index". A better handling of this is to use device index which is allocated by ida. Signed-off-by: Sjur Br?ndeland <sjur.brandeland at stericsson.com> ---

From: Sjur Br?ndeland <sjur.brandeland at stericsson.com> Use virtio device index for creating unique device port names. Current index allocation in virtio is based on a monotonically increasing variable "index". A better handling of this is to use device index which is allocated by ida. Signed-off-by: Sjur Br?ndeland <sjur.brandeland at stericsson.com> ---

Hey Rusty, These updated patches in the series return -EFAULT on copy_xx_user errors and also move the copy_from_user into fops_write() instead of it being in send_buf. This enables send_buf to just read from kernel buffers, making it simpler. This also allows write()s to write more to the host in one go, removingthe 4k limitation. I do limit the writes to 32k at once to not put too much

Hey Rusty, These updated patches in the series return -EFAULT on copy_xx_user errors and also move the copy_from_user into fops_write() instead of it being in send_buf. This enables send_buf to just read from kernel buffers, making it simpler. This also allows write()s to write more to the host in one go, removingthe 4k limitation. I do limit the writes to 32k at once to not put too much

A crash was observed when a device gets removed while a port is in use. When the port gets removed, we tried to free vq buffers. The vq no longer exists at this stage, just ensure we don't access it. The second patch fixes a warning where the pci region is already freed. I'm not sure what or how the region gets freed, any clues there will be helpful. Thanks, Amit Amit Shah (2):

A crash was observed when a device gets removed while a port is in use. When the port gets removed, we tried to free vq buffers. The vq no longer exists at this stage, just ensure we don't access it. The second patch fixes a warning where the pci region is already freed. I'm not sure what or how the region gets freed, any clues there will be helpful. Thanks, Amit Amit Shah (2):